| results of testing for intestinal parasites by state diagnostic laboratories, united states, 1987. | we analyzed results of 216,275 stool specimens examined by the state diagnostic laboratories in 1987; parasites were found in 20.1%. percentages were highest for protozoans: giardia lamblia (7.2%), entamoeba coli and endolimax nana (4.2% each), blastocystis hominis (2.6%), entamoeba histolytica (0.9%), and cryptosporidium species (0.2%). identifications of giardia lamblia increased broadly from the 4.0% average found in 1979, with 40 states reporting increases and seven decreases. most states th ... | 1991 | 1779956 |